In a hospital, a nursing-and-caring facility, or the like, it may be installed a nurse call system which allows a patient and a nurse (a person to be cared and a care worker in a case of a nursing-and-caring facility or the like) to have a telephone conversation therebetween. Such a nurse call system is a system in which a nurse call apparatus and a private branch exchange (PBX, or a key telephone master unit) operate in association with each other, and a nurse call master unit accommodates nurse call slave units allocated to patients (or beds) in sickrooms, respectively. Also, each of nurses carries a portable terminal (such as a personal handy-phone system (PHS) terminal, a personal access system (PAS) terminal, and the like, which will hereinafter be referred to as a “PHS terminal”), and the portable terminal is configured so as to be accommodated in a private branch exchange via a radio line.
For a patient to summon a nurse, the patient makes a nurse call to an extension number of a PHS terminal from a nurse call slave unit, and the PHS terminal is called up from a nurse call master unit via a private branch exchange, to thereby have a telephone conversation. Conversely, also a PHS terminal can call up a nurse call slave unit of a patient, and have a telephone conversation. Further, in light of nursing in teams, PHS terminals carried by nurses are divided into some teams, and the system is configured such that PHS terminals of a plurality of nurses belonging to one team can be simultaneously called up from a slave unit, to thereby summon nurses who are in charge of a patient at one floor.
An example of the above-described nurse call system is shown in FIG. 5. The nurse call system includes a nurse call controller 20 which accommodates a plurality of nurse call slave units 10 (SU 11-1, 11-2, 11-3, 12-1, 12-2, 12-3, . . . ), a private branch exchange (PBX) 40 which accommodates a plurality of PHS terminals 50 belonging to either of two groups (teams) (PHS terminals 51-1, 51-2, and 51-3 in a first group, and PHS terminals 52-1, 52-2, and 52-3 in a second group) via a radio line, and a nurse call adapter 32 which is interposed between the nurse call controller 20 and the private branch exchange 40 and converts an interface between the nurse call controller 20 and the private branch exchange 40. In this regard, the nurse call controller 20 is a representation of a part of functions which relates to control of communication or the like of a nurse call master unit accommodating the plurality of nurse call slave units 10, and forms a part of the nurse call master unit.
There will be described about connection of the nurse call controller 20 having the above-described structure, to the private branch exchange 40 via the nurse call adapter 32. In FIG. 6, for the sake of explanation, it is assumed that the nurse call slave units 10 include only a slave unit #1, a slave unit #2, a slave unit #3, and a slave unit #4, and that three PHS terminals PHS #1, PHS #2, and PHS #3 belong to one group (group #1) in the PHS terminal 50. Thus, PHS #4 belongs to another group. As shown in FIG. 6, the nurse call adapter 32 achieves connection by connecting the nurse call controller 20 to an analog line unit 43 accommodated in the private branch exchange 40. The nurse call adapter 32 relays two lines with four speech paths (channels) included in the nurse call controller 20 to eight analog lines with eight speech paths included in the analog line unit 43. That is, data channels of four channels of ISDN basic interface (2B+D)×2 of the nurse call controller 20 is converted into an analog line, to achieve connection to the analog line unit 43 of the private branch exchange 40.
As a result of this, as shown in FIG. 6, a channel #1 of the nurse call controller 20 is converted into an analog line with channels, the number of which correspond to the number of PHS terminals in the group #1, in the nurse call adapter 32, and the channels are contained in a channel #1, a channel #2, and a channel #3 of the analog line unit 43 of the private branch exchange 40, and connected to channels #1-3 of the private branch exchange 40, so that some (PHS #1 to PHS #3) of the PHS terminals 50, the number of which correspond to the number of extension terminals in the group #1 of the private branch exchange 40 can be called up.